Hello,
I have two files. File1 is normal txt file and File2 contains list of line numbers.
e.g. File2:
I need to replace a character in File1 in lines (taken from File2). For that I am using a "for" loop:
but my files contain million numbers and for loop is taking a long time. can I use a faster approach?
Thanks......
Last edited by Scott; 07-21-2011 at 03:57 PM..
Reason: Please use code tags, and a subject title that better reflects your problem
I know we can substitute a string using sed but how?
For example: sed 's/(old variable)/(new variable)/ details.dat
Am I suppose to put $old variable or whatever? Because I tried many times, it didnt work by putting $old variable. Am I suppose to enclose it with "" or ''?
Please help (3 Replies)
Hi,
I have a set of files containing strings like I.TEST1_TEST2 or B.ESSA_ESSB for example.
Does somebody know how to substitute these strings whith the same name and an extension "_V1" (ie. I.TEST1_TEST2_V1) using sed command or else ? (3 Replies)
Hi ,
I am stuck up in the below scenario:-
I need to read a file name (eg A.txt) name frm another file (eg B.txt) and then I need to search for a particular expression in A.txt and substitute it with another expression.
How can I use SED inside SHELL Scripting and command prompt as... (2 Replies)
Hi ,
I am stuck up in the below scenario:-
I need to read a file name (eg A.txt) name frm another file (eg B.txt) and then I need to search for a particular expression in A.txt and substitute it with another expression.
How can I use SED inside SHELL Scripting and command prompt as well to... (1 Reply)
Hi guys,
Can u please help me to replace (-) with (/) in a file containing no of records using "sed " command in unix.
thanks in advance.
subhendu (5 Replies)
Hi I am trying to do a text insertion in a text file at a particular line number in a shell script. However its not working.
sed '122i\
> for j in \`echo $MyList\` ; do perl -pi -e\'s#01\/01\/2009#01\/01\/2011#\' $j ; done' $HOME/MyScript.ksh
The Actual line to be inserted at line 122... (5 Replies)
I'm a noob to unix, and I have a line of data like the following:
title=Boston|tcolor=green|desc=Large city in New England|url=www.boston.com
Is there a way to change a field value with sed substitution?
(i.e. change tcolor=green to tcolor=blue)
I figured out: sed... (19 Replies)
I have a file with some numbers having single quotes around them which I want to remove.
i.e. '923930' -> 23930
If it can be done without using sed thats fine. I have tried with sed but can't think how to replace this pattern on only the numbers (13 Replies)
How can you use sed with a line of code that reads:
67899:Bill:Williams:Maple Dr.:45908600
Let us say we want to replace Maple Dr. with Oak St. (1 Reply)
Hi everyone,
I need very simple sed command to change a parameter in a text file.
I have a line in this text which is like
set xx 0.5
A program reads this file and does some algebraic calculations. So to make a parameter scan I need to change the value of xx. I thought I can do... (7 Replies)
Discussion started by: hayreter
7 Replies
LEARN ABOUT REDHAT
ppmtosixel
ppmtosixel(1) General Commands Manual ppmtosixel(1)NAME
ppmtosixel - convert a portable pixmap into DEC sixel format
SYNOPSIS
ppmtosixel [-raw] [-margin] [ppmfile]
DESCRIPTION
Reads a portable pixmap as input. Produces sixel commands (SIX) as output. The output is formatted for color printing, e.g. for a DEC
LJ250 color inkjet printer.
If RGB values from the PPM file do not have maxval=100, the RGB values are rescaled. A printer control header and a color assignment table
begin the SIX file. Image data is written in a compressed format by default. A printer control footer ends the image file.
OPTIONS -raw If specified, each pixel will be explicitly described in the image file. If -raw is not specified, output will default to com-
pressed format in which identical adjacent pixels are replaced by "repeat pixel" commands. A raw file is often an order of magni-
tude larger than a compressed file and prints much slower.
-margin
If -margin is not specified, the image will be start at the left margin (of the window, paper, or whatever). If -margin is speci-
fied, a 1.5 inch left margin will offset the image.
PRINTING
Generally, sixel files must reach the printer unfiltered. Use the lpr -x option or cat filename > /dev/tty0?.
BUGS
Upon rescaling, truncation of the least significant bits of RGB values may result in poor color conversion. If the original PPM maxval was
greater than 100, rescaling also reduces the image depth. While the actual RGB values from the ppm file are more or less retained, the
color palette of the LJ250 may not match the colors on your screen. This seems to be a printer limitation.
SEE ALSO ppm(5)AUTHOR
Copyright (C) 1991 by Rick Vinci.
26 April 1991 ppmtosixel(1)